Originally Posted by Milkfred
As for the Emperor, the infamous scene where he admits to being a monster is more complicated than people give it credit for. The big thing to remember is that, at that point, the Emperor is getting exasperated with the player. The discussion is, basically, paraphrased:

"I don't trust you."
"What if I show you my thoughts, will you trust me then?"
"I'll never believe anything you show me."

So... why does the Emperor show you something heinous? Because he's provoking you. He shows you something bad and the player, after saying they won't believe him, probably leap on the 'I knew it! You're a monster!' answer and, yes, then the Emperor basically has an exasperated tantrum. But he's right, too. He could just mind control you and make you do what he wants. But he doesn't. He goes out of his way to not do that. If you pull a dog's tail for weeks, and it barks at you, is it a monster? Or should you have known better?

There are other tidbits that hint that the version of events he reveals is not true, such as Stelmane apparently living a pretty okay life after the "Mind Flayer attack", and that the Knights of the Shield were apparently a devil-worshipping group.
The last bit isn't really true though. If you read the patient log in the parts of the Elfsong tavern basement that connect to the undercity, it is revealed that without the Emperor's control Stelmane became lethargic, indicating that she's just a hollowed out puppet used by the Emperor. So yeah, the vision the Emperor reveals to us in anger seems to align more with reality - even if it reaffirms our personal biases.
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[A journal stamped with the official seal of Duke Belynne Stelmane. It appears to be an attendant's log of the care given during the Duke's ongoing illness. The most recent entries detail a deterioration in the Duke's condition.]

Can't explain the relapse. Duke lacks appetite, awareness, or interest in anything. Occasionally asks after visitor, which I suspect might be cause of current condition.

Duke used to receive visitor in private every tenday - always hooded and cloaked, always shown in and left to attend Duke privately. No luck in finding - oddly enough, can't recall visitor's gender, or even stature - could be half-orc or halfling for all I know.

Hoping for their return - visits appeared to ease the Duke's mind and body greatly.